“Um, yeah, my question is kind of broad?” begins a gawky guy who identifies himself as a Tufts student interning in Client Solutions. “Earlier this summer we had the LIBOR scandal that was involved with a lot of the big banks and led to the resignation of the CEO from Barclays. More recently we had Sandy Weill saying the banks needed to be broken up. With the banks so big, how is it possible to monitor every aspect?”

Next up is a scruffy-haired kid from the University of Miami: “With banking in a secular or cyclical decline, do you truly believe that this is a good place for us to start our careers, considering all of the other opportunities available to us?” he asks.

“In an industry associated with surprisingly low standards … ” a woman from Emory University starts to say.

“Whoa, whoa, whoa,” the JPMorgan Chase CEO interrupts, leaning into the microphone and peering out at the several hundred summer interns, sweating in their first business clothes, that have gathered in the auditorium of the former Bear Stearns building for a friendly Q&A session with the boss. “Before you go to the next level of generalizing, saying, ‘all bankers,’ ‘all banks.’ I don’t like that.” The room murmurs its assent as Dimon, pacing onstage in his summer uniform of a suit and no tie, warms to his topic. “I don’t buy this thing that our industry is responsible for all the ills of the world. We have great people at JPMorgan Chase. We operate with a lot of rigor. Our clients are happy with us. Sure, we make mistakes, like we have got this Whale thing. Businesses make mistakes. So we’ve got to clean them up, learn from them, and get better. And I want you to know the London Whale issue is dead,” he says. “The Whale has been harpooned. Dessicated. Cremated.” His voice carries over the students’ laughter. “I am going to bury its ashes all over.”

He’d certainly like to. But, “there’s a tail,” he concedes to me on a recent morning, sitting in his 48th-floor office, a homey space filled with knickknacks and family photos that requires passage through a gauntlet of machines and a security guard escort to reach. He means “tail” in the business-y sense, as in: The trading scandal that rocked the firm at the beginning of the year will have lasting repercussions. If he finds it at all amusing that actual whales have tails, he doesn’t show it. With his boyishly wavy hair and down-home platitudes, Dimon can come across like an overgrown frat boy. (“Don’t sell a product to anyone you wouldn’t sell your motha,” he likes to warn employees, in his Marky Mark–via–Queens accent.) But when it comes to this topic, he’s sober as a judge. You wouldn’t say his swagger has been trampled, more effortfully tempered. “I never get anxious,” he announces at one point. “I don’t normally.” This spring, though, was different.

At first, when questions came up about the activities of Bruno Iksil, a trader in the London-based Chief Investment Office who had taken such a massive position in the credit market that it caused waves in the sector (hence the nickname), Dimon was dismissive. “It’s a complete tempest in a teapot,” he told analysts, a comment that would come back to haunt him when repeated, ad nauseam, in escalating news stories that reported the London Whale’s activities had cost the firm $2 billion, then $3 billion, then close to $6 billion and counting.

“I had been told a whole bunch of stuff that made me think it was a tempest in a teapot,” he says now, adding that it was only when he laid eyes on the positions that he realized the extent of the problem. “There was a moment of, I can’t believe what we have.” For Dimon, who had boasted in the past of the bank’s risk management and “fortress balance sheet,” the blunder was particularly, specifically embarrassing, like Jerry Falwell getting caught with a hooker. “I saw it all pass in front of my eyes,” he says. “I saw the headlines, the investigations, the uproar, the breathlessness. ‘Dimon Loses Luster,’ ‘Dimon in the Rough.’ I told everyone, ‘This is going to be bad, it’s going to go on, and we can’t get out of it. So put your jerseys on: We’re going to wrestle this thing down and fix it.’ ” He went on Meet the Press: “We made a terrible, egregious mistake,” he told David Gregory, his Droopy-the-dog eyes conveying sincerity. Iksil and those who oversaw him were swiftly disappeared; top management was reorganized. “We had to review thousands of e-mails, minutes of tapes,” Dimon recounts. “We cleaned up the risk. It scared the daylights out of our people. We crossed the t’s and dotted the i’s and put in new rules, and we’re fine.” He says all this quickly, as though he’s told this story a million times and thinks this should have been the end of it.